JP7251863B2 - denture attachment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a denture attachment, and more particularly, a user can easily connect a first fastening part coupled to a denture and a second fastening part provided on the upper side of a natural tooth or an implant fixture. In addition to being able to be put on and taken off with a gentle operation, even if occlusal force is continuously applied to the denture, the force transmitted by the elastic rib structure of the attachment itself can be buffered, and as a result, the life of the attachment itself is shortened. It is possible to prolong the life of the implant fixture or the root of the natural tooth, and the plurality of fixtures implanted in the alveolar bone have a large deviation from each other so that the implantation angle formed by each other is 50° or more. The present invention relates to a durable denture attachment that allows a first fastening portion to be fastened to a second fastening portion without any interference or deformation, even when the attachment is implanted in the same manner.

Dentures are a kind of treatment method that replaces damaged permanent teeth, and are widely used because they are less economical than implant-type artificial teeth. Such dentures are removably coupled to the user's gums, for example, they can be separated from the gums when cleaning or going to bed, and coupled to the gums when eating or going out. can do.

In general, the retention force of dentures is reinforced by denture attachments, and conventional denture attachments have a second fastening portion located on the upper side of a fixture implanted in the alveolar bone of the human body. The first fastening part embedded in the bottom part of the denture is detachable from each other, and the fastening method is generally that the second fastening part is made of metal and is connected to the bottom surface of the denture. The first fastening portion used is a fastening method that utilizes the elastic force of a plastic or rubber ring by positioning a polymer such as a plastic or rubber ring in a narrow space inside a housing made of metal.

However, in such a conventional denture attachment, there is a second fastening part made of metal located on one side of the fixture, and a plastic or plastic material placed in a narrow space in the metal housing embedded in the bottom surface of the denture. Since the first fastening part on which the elastic body made of rubber is located is attached and detached, as the denture is used for a longer period of time, the plastic and rubber materials are worn out, and the denture is broken due to the occlusal force applied to the denture in various directions. There is a problem that the durability is deteriorated, such as breakage of the polymer material such as plastic or rubber, due to the continuous application of stress to the attachment while the position keeps changing.

In addition, the longer the denture is used, the more worn the plastic or rubber ring in the metal housing of the first fastening part, the denture is not firmly fixed to the gums and shakes. There was also the problem of

Furthermore, the above-mentioned prior art has a material limitation in the cushioning function that the very small plastic or rubber in the metal housing of the first fastening portion can exhibit within the elastic deformation limit, so the denture cannot be worn. The chewing force generated when chewing food in this state is directly transmitted from the denture to the fixture. At this time, there is a problem that the attachment or the fixture is deformed and damaged due to the mastication force being concentrated on the fixture, which is inconvenient due to the frequent need for maintenance of the attachment and maintenance costs. There was a problem that it took too much.

In particular, in general, when occlusal force is applied to dentures, the gums that are in contact with the bottom surface of the dentures are pressed and contracted, and as a result, the position of the dentures placed on the gums is also displaced toward the gums by the amount of contraction. It often happens that When such occlusal force is continuously applied to the denture and the denture continues to be displaced toward the gums, such occlusal force intensively transmits excessive force to the attachment or fixture, shortening the service life. I had a problem getting it to work.

Therefore, not only can the user attach and detach the denture with a simple operation, but even when mastication force or bite force is continuously applied to the denture, the force transmitted by the structural features of the attachment itself can be buffered. A removable denture attachment is required.

In addition, conventional attachments are of the type in which a non-metallic polymer such as a plastic or rubber ring is attached to a narrow space in a metal housing embedded in the bottom of the denture to utilize the elasticity of the polymer. Due to material limitations, it is difficult to obtain sufficient elasticity and durability required for attaching and detaching dentures. A metal housing is required, and when such a metal housing is embedded in the bottom surface of the denture, it often protrudes buccal or lingually of the denture. For this reason, an attachment that has sufficient elasticity and durability but is as small as possible is required.

Furthermore, the conventional attachment is to implant a plurality of fixtures in the alveolar bone, position corresponding parts on the top of the plurality of fixtures, and embed a plurality of corresponding fastening parts to the bottom surface of the denture. In other words, when using multiple attachments, if the angles of the fixtures planted in the alveolar bone are not parallel to each other and are deviated by 20° or more, the angle at which each attachment can be fastened is limited. Due to the limitation, the corresponding part located on the upper part of the fixture cannot be used as a generally used straight type corresponding part, and a special corresponding part called an angled abutment is used. In addition to the cumbersome problem of having to compensate for widely differing implantation angles with a slanted abutment, a slanted abutment compensates for all angles, even if a special slanted abutment counterpart is used. There was a problem that it was impossible to produce all the various angles as possible. Therefore, there is a demand for a denture attachment that can solve the problem with a single corresponding part even if the erection angles of the fixtures are greatly different.

Another conventional technique, the hook fastening method, is formed by a simple straight incision in the direction of the gums from the flange embedded in the bottom of the denture because the distance from the flange embedded in the bottom of the denture to the gums is too short. With short-length hook projections, it is impossible to obtain sufficiently soft, appropriate elastic force, durability, and appropriate denture retention force required for repeated attachment and detachment of dentures. As a result, the attachment suddenly loses its elasticity in a short period of time, and the occlusal force that continues to be applied in various directions while the denture is attached in the oral cavity prevents the movement of the denture in all directions, including front, back, left, and right. Since it is not possible to exert a stress break function that buffers the tension, there is a problem that the short length of the hook projection is likely to be permanently deformed, and the continuous impact of the unbuffered bite force causes the fixture to break. There is a problem that the service life may be shortened.

An object of the present invention is to allow a user to easily attach and detach a first fastening portion coupled to the bottom surface of a denture and a second fastening portion provided on the upper side of a natural tooth or an implant fixture. In addition, even if the occlusal force is continuously applied to the denture, the force transmitted by the elastic rib structure of the attachment itself can be buffered, as a result, not only the life of the attachment but also the second fastening part To provide an attachment for dentures capable of prolonging even the life of an implant fixture to which a tooth is bonded or the root of a natural tooth.

Another object of the present invention is to configure the attachment itself to have a cushioning function with a plurality of helical elastic ribs, so that the stress applied by the occlusal force is cushioned and does not concentrate on the attachment or the implant fixture. A further object of the present invention is to provide a denture attachment that can absorb stress due to vertical and lateral pressure.

Another object of the present invention is to achieve a second fastening even when a plurality of fixtures implanted in the alveolar bone are implanted at an angle of 50° or more with a large deviation from each other. By having the neck of the fixture seat in the fixture installation angle-receiving recess, it is possible to compensate for the offset installation angle of the fixture, so that the installation angle formed by the fixture is To enable a first fastening part to be fastened to a second fastening part without any interference or deformation even when they are planted at an angle of 50° or more from each other.

Another object of the present invention is to form a slanted surface from the outer diameter to the inner diameter of the distal end of the first fastening portion embedded in the bottom surface of the denture, so that the denture is attached to the gum frame in the process of attaching the second fastening portion to the gum frame. Even if the second fastening portion does not come to the correct position where it can be coupled with the first fastening portion, the second fastening portion slides along the inclined surface from the outer diameter to the inner diameter of the entrance of the first fastening portion. An object of the present invention is to provide a denture attachment that can be naturally coupled with a first fastening part because it is positioned in a movable manner.

One embodiment of the present invention for achieving the above object is a denture attachment used to reinforce the retention force of a denture worn in the oral cavity, the denture attachment being attached to the bottom surface of the denture. 1 fastening part, and a second fastening part provided on the upper side of the natural tooth or implant fixture implanted in the alveolar bone and mutually coupled with the first fastening part, At least one of the fastening portion and the second fastening portion is provided with a plurality of elastic ribs having a spiral shape in a predetermined section along the outer circumference centered on the inner diameter central axis, and each unit elastic rib is , one end is connected to each other and the other end is separated from each other, so that the other end is deformed inward or outward with respect to the central axis of the inner diameter by an external force, and then restored to its original shape when the external force is removed. The first fastening portion and the second fastening portion are configured to be elastically detachable by the elastic restoring action of the elastic ribs.

According to the present invention, the user can easily attach and detach the first fastening portion coupled to the bottom surface of the denture and the second fastening portion provided on the upper side of the natural tooth or implant fixture. In addition, even if the occlusal force is continuously applied to the denture, the force transmitted by the elastic rib structure of the attachment itself can be buffered, as a result, not only the life of the attachment but also the second fastening part It has the effect of prolonging the life of the implant fixture or even the root of the natural tooth to which is bonded. In addition, by configuring the attachment itself to have a cushioning function with a plurality of helical elastic ribs, the stress applied by the occlusal force is cushioned and is not concentrated on the attachment or the implant fixture. Pressure stress can also be distributed throughout.

In addition, according to the present invention, at least one of the second fastening portion located on one surface of the fixture and the first fastening portion embedded in the bottom surface of the denture is provided with a plurality of helical fixed sections. An elastic fastening part formed by collecting elastic ribs is provided, and the open end of the elastic rib having a spiral shape in a certain section is elastically moved inward or outward around the central axis of the inner diameter of the elastic rib. By forming elastic ribs to have an elastic fastening force, the length of the elastic ribs can be extended at least 2.5 times longer than when the elastic ribs are formed linearly to have a fastening force. The amount of elastic deformation without permanent deformation of the elastic ribs of the shape can be greatly increased. Fixtures or attachments can also exhibit a pressure relief function that can partially elastically allow denture movement in all directions including front, back, left, and right that can occur when occlusal forces are applied in various directions. have the effect of prolonging the life of

In addition, when a plurality of fixtures implanted in the alveolar bone are implanted with a large deviation from each other such that the implanting angle formed by the fixtures is 50° or more, the neck portion of the second fastening portion is the fixture. By being seated in an installation angle accommodation recess, it is possible to compensate for an offset installation angle of the fixture so that the installation angle of the fixture is greater than 50°. This has the effect that the first fastening portion can be fastened to the second fastening portion without any interference or deformation even if they are planted with a large deviation from each other.

In addition, according to the present invention, the end portion of the first fastening portion embedded in the bottom surface of the denture forms an inclined surface from the outer diameter to the inner diameter. Even if the second fastening portion does not come to the correct position where it can be coupled with the first fastening portion, the second fastening portion slides along the inclined surface from the outer diameter to the inner diameter of the entrance of the first fastening portion. Since it is moved and positioned, it has the effect that it can be naturally coupled with the first fastening portion.

1 is an exploded perspective view of a denture attachment according to one embodiment of the present invention; FIG. 1 is an exploded cross-sectional view of a denture attachment according to one embodiment of the present invention; FIG. 1 is a perspective view, a cross-sectional view along line AA, and a cross-sectional view along line BB showing an embodiment of a first fastening portion of the present invention; FIG. 1 is a combined cross-sectional view of a denture attachment according to an embodiment of the present invention; FIG. In one embodiment of the present invention, when the first fastening portion is coupled to the second fastening portion with the vertical central axis of the second fastening portion being offset, the neck portion of the second fastening portion is positioned at the second fastening portion. 1 is a cross-sectional view showing a structure of a fastening portion 1 seated in a recessed portion for accommodating a fixture erection angle; FIG. FIG. 6(a) is a perspective view showing another embodiment of the first fastening portion of the present invention, and FIG. 6(b) is a perspective view showing another embodiment of the first fastening portion of the present invention. FIG. 5 is a perspective view showing the structure of a second fastening part according to another embodiment of the present invention; FIG. 8 is a cross-sectional view showing the structure of a second fastening portion and the structure of a first fastening portion coupled to the second fastening portion according to another embodiment of the present invention; FIG. 4 is a cross-sectional view showing another embodiment of an elastic rib protection housing for protecting elastic ribs according to an embodiment of the present invention; FIG. 10 is a perspective view, a cross-sectional view along line AA, and a cross-sectional view along line BB showing another embodiment of the first fastening portion of the present invention; FIG. 4 is a cross-sectional view showing an inclined surface S from the outer diameter to the inner diameter of the distal end of the first fastening portion according to one embodiment of the present invention;

Preferred embodiments of the present invention will now be described in more detail with reference to the drawings.

FIG. 1 is an exploded perspective view of a denture attachment according to one embodiment of the present invention, and FIG. 2 is an exploded sectional view of the denture attachment according to one embodiment of the present invention.

First, referring to FIGS. 1 and 2, a denture attachment 100 according to an embodiment of the present invention is used to reinforce the retention force of dentures worn in the oral cavity, and contacts the gums. and a first fastening portion 20 extending below the base portion 10 and having a plurality of elastic ribs 20A and 20B protruding downward along the outer periphery thereof. and a second fastening part 40 provided on the upper part of the root of the natural tooth implanted in the alveolar bone or on the upper part of the implant fixture 1 and mutually coupled with the first fastening part 20 . Preferably, the base part 10 and the first fastening part 20 are connected to the denture so as to be embedded in the denture body.

Although FIGS. 1 and 2 show that the abutment 30 having the second fastening part 40 is coupled to the upper side of the implant fixture 1, the second fastening part 40 can be formed in various ways. It can be provided on the upper side of a natural tooth or an implant fixture, or alternatively, it can be integrally formed with a fixture that is implanted in the alveolar bone.

The base part 10 and the second fastening part 40 are fixed inside the denture body with an adhesive resin or the like. More preferably, it is self-evident that the base part 10 can be manufactured in various shapes as long as it has the function of being fixed to the denture.

As shown in FIGS. 1 and 2, the first fastening part 20 extends below the base part 10 and has a plurality of spiral elastic ribs 20a and 20b formed at the same inner diameter center. It is provided so as to protrude downward along the outer periphery with the axis A as the center. Preferably, the elastic ribs 20a and 20b of the unit are connected to each other at one end and separated from each other at the other end, so that the other end is deformed inwardly or outwardly with respect to the same inner diameter central axis A by an external force, and then When the external force is removed, the original shape is restored, and the elastic restoring action of these elastic ribs allows the first fastening part 20 and the second fastening part 40 to be elastically attached and detached.

On the other hand, as shown in FIG. 7, the second coupling part 40 may also be provided with a plurality of spiral elastic ribs around the same inner diameter central axis A along the outer circumference. That is, in at least one of the first fastening portion 20 and the second fastening portion 40, a plurality of elastic ribs having a spiral shape in a predetermined section are formed along the outer circumference centering on the same inner diameter central axis A. can be provided.

Referring to FIG. 1, the attachment 30 is fastened to the upper part of the root of the natural tooth implanted in the alveolar bone or the upper part of the implant fixture 1, and is detachable from the first fastening part 20. A second fastening portion 40 is provided for coupling to. That is, the thread 32 of the attachment 30 is screwed into the shaft hole of the implant fixture 1 and fixed.

Referring to FIG. 2, a second fastening part 40 protruding from the top of the attachment 30 is coupled to a fastening space formed inside by being surrounded by a plurality of elastic ribs 20a and 20b. That is, the user simply presses the entire denture downward while the first fastening portion 20 fixed to the denture by the adhesive resin is positioned above the second fastening portion 40. The denture can be easily mounted on the gums with a clicking sound. Here, when the first fastening portion 20 composed of the plurality of elastic ribs 20a and 20b is fastened to the second fastening portion 40, the plurality of elastic ribs 20a and 20b have the same inner diameter vertical center. It is elastically fastened to the second fastening part 40 by an elastic restoring action of being deformed outwardly or inwardly with respect to the axis A and then restored to its original state when the fastening is completed. In some cases, the second fastener can be integrally formed with the implant fixture.

Referring to FIG. 1, the first fastening part 20 includes a plurality of elastic ribs 20a and 20b having a spiral shape over a certain section. , itself has a cushioning function, so it not only cushions the stress applied by the occlusal force, but also disperses the stress due to vertical and lateral pressure.

FIG. 6(a) is a perspective view showing one embodiment of the first fastening portion of the present invention, and FIG. 6(b) is a perspective view showing another embodiment of the first fastening portion of the present invention. . The plurality of elastic ribs 20a, 20b of the present invention may be spirally formed to the lower end of the first fastening part 20, as shown in FIG. 6(a), as shown in FIG. 6(b). , it may have a helical shape in a certain section and may be formed straight from the end. In this case, there is a helical gap 22 between adjacent elastic ribs at the top and a vertical gap 24 in certain sections at the ends. The reason why the vertical gaps 24 are formed in this way, especially at the ends that are open at the bottom, is to ensure sufficient mechanical strength of the elastic ribs. If the elastic rib is formed in a spiral shape from the base part 10 to the lower end of the first fastening part 20 as shown in FIG. I considered the possibility. However, the present invention should be construed as including all structures in which the plurality of elastic ribs can have a helical shape in at least a certain section of the first fastening portion 20 .

Referring to FIGS. 1 and 3, at the end of the first fastening part 20 formed of the other end of the separated elastic rib, there is at least one recessed part 22 for accommodating the fixture erection angle recessed for a certain period. one is formed.

When the fixture erection angle accommodating depressions 22 are erected with a large deviation from each other so that the erection angle between the fixtures is 50° or more, as shown in FIG. By having the neck portion 42 of the fastener 40 seat in the fixture planting angle-receiving recess 22, the offset planting angle of the fixture can be compensated for, resulting in a fixture that is Even if they are planted at an angle of 50° or more, the first fastening portion can be fastened to the second fastening portion without any interference or deformation.

Referring to FIG. 5, the fixture erection angle accommodation depression 22 has a first fastening part 20 that couples with a second fastening part 40 that is fastened to the fixtures that are erected with a large deviation from each other. In order to minimize the deformation of the elastic ribs of the first fastening portion by the second fastening portion when the implanted denture moves in the gum direction due to occlusal force after being worn in the oral cavity, the elastic ribs are separated. The end portion of the first coupling portion, which is the other end of the elastic rib, that is, the second coupling portion is formed to be depressed for a certain section at the initial entrance portion of the first coupling portion.

Preferably, as shown in FIG. 2, the width D3 of the fixture erection angle accommodation depression 22 is equal to or greater than the maximum outer diameter D4 of the neck 42 of the second fastening portion 40 . As a result, when the first fastener is coupled to the second fastener with the vertical central axis of the second fastener displaced, the neck portion 42 of the second fastener is at the fixture installation angle. It can be seated in the receiving recess 22 so that the fixture installation angle receiving recess of the first fastener is closest to the outer surface of the lower neck portion of the second fastener. can.

Referring to FIG. 1, an elastic rib protection housing 50 may be further provided on the outer peripheral surfaces of the plurality of elastic ribs 20a and 20b. The elastic rib protection housing 50 prevents the adhesive resin used for fixing the first fastening part 20 to the denture from penetrating between the elastic ribs 20a and 20b of the first fastening part 20. , which can be integrally provided with the base part 10, or can be manufactured separately so that it can be removed after the fixing work of the base part is completed. Preferably, the elastic rib protection housing 50 deforms the elastic ribs in the elastic rib protection housing 50 when the first fastening part 20 is fastened to the second fastening part 40 or when an occlusal force is applied to the denture. The inner surface of the elastic rib protection housing 50 and the outer surface of the first fastening part 20 can be manufactured to have a gap corresponding to the space for elastic deformation so that a sufficient space can be secured.

According to another embodiment of the present invention, as shown in FIG. 9, the outer peripheral surface of the elastic rib protection housing 50 may be further provided with an uneven portion 52 . This is because, when the base part 10 and the elastic rib protection housing 50 are entirely embedded in the denture with resin, the uneven part 52 is combined with the resin to ensure firmness and durability. Preferably, the elastic rib protection housing 50 has wrinkles along the circumference so that it can be folded in a vertical length direction at a certain interval to shorten the length. In some cases, the elastic rib protection housing 50 may be made of a synthetic resin material such as a polymer to facilitate wrinkling.

According to another embodiment of the present invention, as shown in FIGS. 6 and 7, the first fastening part 20 may have a structure fastened to the second fastening part 40 consisting of a plurality of elastic ribs. . In this case, when the first fastening part 20 is inserted and fastened, the plurality of elastic ribs of the second fastening part 40 are deformed outward with respect to the central axis A and then restored to their original state when fastening is completed. It is elastically fastened by the elastic restoring action of the joint.

Referring to FIG. 4, when the first fastening part 20 and the second fastening part 40 are fastened together, the axis of the first fastening part 20 is surrounded by a plurality of elastic ribs having a helical shape for a certain section. Between the bottom surface of the hole and the upper end of the second fastening part 40, a 'vertical position change accommodation space B for the denture' may be formed. Preferably, the vertical distance of said accommodation space B amounts to at least 0.6 mm. More preferably, an elastic body such as a spring or a rubber material may be further provided in the vertical position change accommodating space of the denture. Most preferably, the inner diameter D1 of the denture vertical position change accommodating space B is equal to or larger than the maximum outer diameter D2 of the fastened part of the second fastening part 40 . This is because when the gums in contact with the bottom surface of the denture are pressed by an occlusal force and the vertical position of the denture changes, the second fastening part 40 can be inserted into the vertical position change accommodation space B without interference of the edges. This is to allow easy entry.

That is, when an occlusal force is applied to the denture and the gums in contact with the bottom surface of the denture are pressed to change the vertical position of the denture, the first fastening portion (that is, While the elastic ribs) are deformed outward, the second fastening part 40 moves into the "vertical position change accommodation space of the denture". After that, when the occlusal force is removed and the pressed gums are restored, the gums move to the position before receiving the occlusal force, the first fastening portion 20 is restored to its original position, and as a result, the second fastening portion 20 is restored to its original position. The fastening part 40 of the first fastening part 20 can be elastically restored to the vertical position before receiving the bite force in the axial hole of the first fastening part 20 . In this case, an elastic body such as a spring or a rubber material is further provided in the space for accommodating the vertical position change of the denture, thereby facilitating the elastic restoration of the denture position.

According to another embodiment of the present invention, as shown in FIG. 10, the upper surface of the base part 10 can be provided with screw members 12 for coupling with the denture body. In this case, the denture body is formed with a coupling groove (not shown) at a position corresponding to the screw member 12 . In addition, a polygonal concave groove 14 is provided on the inner lower surface of the base part corresponding to the screw member 12, which requires the operator to connect the attachment to the denture body or replace the attachment. In this case, a screwdriver or the like can be inserted into the polygonal groove 14 and rotated.

In this way, when the attachment is connected to the denture via the screw member, the attachment can be easily fixed to the denture without the adhesive resin. In particular, if the attachment needs to be replaced due to breakage or damage during use after surgery, it can be easily separated and reconnected using a screwdriver.

Although specific embodiments have been described in detail above with reference to the drawings, the present invention is not limited to such specific structures. Those skilled in the art can make various modifications or changes to the present invention without departing from the technical spirit and scope of the invention as defined in the following claims. can. However, it should be clarified in advance that any of these simple design material modifications or modified structures clearly fall within the scope of the present invention.

Claims (10)

A denture attachment used to reinforce the retention force of a denture worn in the oral cavity,
A first fastening part that couples to the denture, and a second fastening part that is provided on the upper side of the natural tooth or the implant fixture that is implanted in the alveolar bone and that couples to the first fastening part. including
At least one of the first fastening portion and the second fastening portion is provided with a plurality of elastic ribs each having a spiral shape in a predetermined section along the outer circumference centering on the inner diameter central axis (A). , each of the unit elastic ribs has one end connected to each other and the other end separated from each other, so that the other end is deformed inwardly or outwardly with respect to the inner diameter central axis (A) by an external force, and then the external force is removed. restored to its original shape,
A denture attachment, characterized in that the elastic restoring action of these elastic ribs enables elastic attachment and detachment of the first fastening portion and the second fastening portion. When the first fastening portion and the second fastening portion are coupled, a gap between the bottom surface of the shaft hole of the first fastening portion surrounded by a plurality of elastic ribs and the upper end of the second fastening portion. 2. An attachment for dentures according to claim 1, characterized in that it forms a vertical displacement receiving space (B) for the denture. The inner diameter (D1) of the vertical position change accommodating space (B) of the denture is equal to or larger than the maximum outer diameter (D2) of the part to be fastened of the second fastening part, The denture attachment according to claim 2. [Claim 3] The denture attachment according to claim 2, wherein the denture vertical position change accommodating space is further provided with an elastically deformable spring or an elastic body made of rubber. At least one fixture erection angle receiving recess recessed for a certain section is formed at the end of the first fastening part formed by the other end of the separated elastic rib. Item 1. The denture attachment according to item 1. 2. The denture attachment according to claim 1, wherein the distal end of said first fastening portion forms an inclined surface from an outer diameter to an inner diameter. 6. The method according to claim 5, characterized in that the width (D3) of the recess for accommodating the fixture installation angle is equal to or larger than the maximum outer diameter (D4) of the neck of the second fastening part. Attachment for dentures. The denture attachment according to claim 1, further comprising an elastic rib protection housing on an outer peripheral surface of the plurality of spiral elastic ribs. 2. The denture attachment according to claim 1, wherein the inner diameter formed by the end portions of the plurality of spiral elastic ribs is smaller than the maximum outer diameter of the corresponding fastened portion. Further comprising a base formed on the upper surface of the first fastening part, the upper surface of the base is formed with a screw member for coupling with the denture body, and the screw member and the base corresponding to the screw member are formed on the upper surface of the base. 2. The denture attachment according to claim 1, wherein the inner lower surface is provided with a polygonal groove into which a screwdriver can be fitted and rotated.

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